what an oscilloscope recommended for a woman passionate about electronics?

[CharlotteSwiss]

We're having fun now!

thanks rstofer, it's a pleasure to read you, you understand from afar that you have a great passion for this world of electrons 
If only I still had that sound card on the table .. I could do other tests, I would understand a lot ... but it would be enough even a signal generator (therefore ac) to test on the bench .. soon something similar will come!
I reread at least 5 times to understand what you wanted to explain to me, and I learned something: in practice with rigol, we are seeing on the display the yellow track which includes a part of DC, and the blue track without dc (only ac). This shows that the pure AC track has zero volts in the center of the wave, while the DC contaminated track has zero volts with downward offset.
In practice, on channel 2, since there is a condenser, it purified the wave from the DC!
Bringing it all back to my sound card waves, this means that those waves have DC contamination, which the 470uf output capacitor failed to completely eliminate.
(if I remember correctly I had made the measurement of only the L channel AFTER the capacitor on the tp predisposed on the board ..)
This teaches me that: if the AC wave has zero volts in the center, it has no DC contamination inside it, otherwise there is DC!

I saw the mathematical functions in the manual, there will be a lot to learn in that chapter! I have to get there prepared, for this, in small steps I am reading the manual gradually.

Very clear the scheme with Ltspice, I also have that program on the PC, it's not bad.

thanks again for the teaching ... and for the final joke you're right, I have fun when it comes to electronics 
Charlotte

edit:
I add this consideration: if you look at my measurement of the audio signal input to the card (so it is the audio signal that comes out of the PC), we can see that it has a lot of noise, but it is before DC, it has zero volts in the center of the wave !, This teaches me that then in the audio circuits of the card or in the sta540 amplifier, the audio signal acquires the dc ..

[Labrat101]

AS most humans have a very limited hearing range .
    The high you go only your 'Cat' will hear it.     
 I have seen sound equipment that the owner said it sounds Great ... 
 It had more hum than a Bee.  When shown they said .. OH I thought that was the Bass 
  I have a Harmon amp also sounds Good till you see it on a scope But I can't hear what I SEE ..

  I am Glade you Have learned a lot there is so much to gain from experimenting and after a year
  or so you will be telling other were they went wrong 

     

[rstofer]

If only I still had that sound card on the table .. I could do other tests, I would understand a lot ... but it would be enough even a signal generator (therefore ac) to test on the bench .. soon something similar will com.e!

I got along without an Arbitrary Waveform Generator for decades and then I bought the Siglent SDG2082 - a very nice AWG.  But watch the specs!  The 80 MHz spec applies ONLY to sine waves.  Everything else is limited to 25 MHz.  Not that it matters but it is sort of deceptive.  But this applies equally to the SDG2042 AWG and that's pretty nice because the 2042 is a lot more affordable and unless you have some reason to want the higher sine frequency, don't buy the 2082 because you will get 25 MHz non-sine waveforms anyway.

I'm going to recommend you come up with something truly cheap in the interim and buy a really good AWG sometime later.  Like after you recover from buying the scope.  The Siglent is a great AWG!  I can't see messing around with lesser devices.

It's nice to be able to select a sine wave output, dial in a frequency and amplitude, maybe add in some DC offset and then push the output button and have the waveform come pouring out of the wires.

https://www.batronix.com/shop/siglent/SDG2000X.html

The reason I could do without an AWG is that I do digital and I can generate square wave streams with microcontrollers or FPGAs.  I seldom work with sine waves and I never mess around with audio or radio.

[tautech]

Honestly the much cheaper SDG1032X would serve Charlotte just as well.

[rstofer]

Honestly the much cheaper SDG1032X would serve Charlotte just as well.

I had forgotten about the SDG1032X.  In the US, it costs about $359 while the SDG2042X costs about $499.
https://www.amazon.com/s?k=sdg103&ref=nb_sb_noss_2
I'm not sure about the differences but saving $140 is certainly worth thinking about.

It is nice to have a highly capable AWG.

[CharlotteSwiss]

AS most humans have a very limited hearing range .
    The high you go only your 'Cat' will hear it.     
 I have seen sound equipment that the owner said it sounds Great ... 
 It had more hum than a Bee.  When shown they said .. OH I thought that was the Bass 
  I have a Harmon amp also sounds Good till you see it on a scope But I can't hear what I SEE ..

  I am Glade you Have learned a lot there is so much to gain from experimenting and after a year
  or so you will be telling other were they went wrong 

I did not understand much with the translator, but you are certainly right
 

[CharlotteSwiss]

If only I still had that sound card on the table .. I could do other tests, I would understand a lot ... but it would be enough even a signal generator (therefore ac) to test on the bench .. soon something similar will com.e!

I got along without an Arbitrary Waveform Generator for decades and then I bought the Siglent SDG2082 - a very nice AWG.  But watch the specs!  The 80 MHz spec applies ONLY to sine waves.  Everything else is limited to 25 MHz.  Not that it matters but it is sort of deceptive.  But this applies equally to the SDG2042 AWG and that's pretty nice because the 2042 is a lot more affordable and unless you have some reason to want the higher sine frequency, don't buy the 2082 because you will get 25 MHz non-sine waveforms anyway.

I'm going to recommend you come up with something truly cheap in the interim and buy a really good AWG sometime later.  Like after you recover from buying the scope.  The Siglent is a great AWG!  I can't see messing around with lesser devices.

It's nice to be able to select a sine wave output, dial in a frequency and amplitude, maybe add in some DC offset and then push the output button and have the waveform come pouring out of the wires.

https://www.batronix.com/shop/siglent/SDG2000X.html

The reason I could do without an AWG is that I do digital and I can generate square wave streams with microcontrollers or FPGAs.  I seldom work with sine waves and I never mess around with audio or radio.

I would start with something cheaper maybe ...
I had thought of a signal to detect a fault in any card, not just audio. I don't think I need a very high frequency? Then in the future if I feel limited, I buy some nice awg
thanks 

[CharlotteSwiss]

Honestly the much cheaper SDG1032X would serve Charlotte just as well.

I could start with something cheaper, I have already spent a lot with the oscilloscope 

[tggzzz]

Honestly the much cheaper SDG1032X would serve Charlotte just as well.

I could start with something cheaper, I have already spent a lot with the oscilloscope 

Good attitude!

Buy something very cheap.
Use it.
Find what it can and can't do in conjunction with your scope.
When you know what you actually need, throw it away and buy what you need

N.B. the cautions about scope probe shields also apply to signal generator shields. But signal generators can easily be battery powered and are less likely to be connected to "inappropriate" internal points.

Examples, without recommendations!:
https://www.ebay.co.uk/itm/DDS-Function-Signal-Generator-Module-Arbitrary-Waveform-Sine-Triangle-UK/202341913155
https://www.ebay.co.uk/itm/DDS-Function-Signal-Generator-Sine-Triangle-Square-Wave-Frequency-1HZ-500KHz/254207772436
https://www.ebay.co.uk/itm/Farnell-Instruments-FG1-Signal-Function-Generator-with-User-Manual/174340314063

[CatalinaWOW]

For audio work you already own a perfectly satisfactory signal generator - the sound output of your PC.  There is free software to put an image on screen and give you controls similar or identical to a standalone signal generator.

There are cautions and limitations, but the price is right.

1.  If you are concerned about damage to your computer build a simple buffer box.  It will cost a couple of dollars and be a good learning project.

2.  You can't have DC offsets.  But by adding an op-amp summer and a voltage divider to your buffer box this is easy to correct.

3.  Amplitude scaling is a little iffy.  But you have a DMM to check and set levels when you care.  Often the only amplitudes you need can be adequately set with the units: Small, Medium and Large.

As long as you are working in the audio frequency range there are few limitations to this setup.  Practice and learning with this will give you the knowledge you need when (and if) you decide you need something more capable.

Another thing you might look at is the free program Audacity.  In many respects it is a software oscilloscope for digital audio signals (and analog from a sound card).  It is great for looking at what the signals from music should look like at various time scales.  It can also be used to generate audio, but is really intended for mixing music, not signal generation.

[Gyro]

If you're worried about the risks and limitations of your PC audio output then you can generate your own test CD to use with your CD player. Either generate the tracks from scratch using an audio editing package, or use an already available one, eg: https://www.head-fi.org/threads/free-audio-test-cd-to-download.225325/


EDIT: Still available on archive.org:  https://web.archive.org/web/20041012012055/http://www.virtuelvis.com/download/201/testcd.7z

[CharlotteSwiss]

Examples, without recommendations!:
https://www.ebay.co.uk/itm/DDS-Function-Signal-Generator-Module-Arbitrary-Waveform-Sine-Triangle-UK/202341913155
https://www.ebay.co.uk/itm/DDS-Function-Signal-Generator-Sine-Triangle-Square-Wave-Frequency-1HZ-500KHz/254207772436
https://www.ebay.co.uk/itm/Farnell-Instruments-FG1-Signal-Function-Generator-with-User-Manual/174340314063

the first two could be a choice to start. The last old generator seems to me broken, I wouldn't be able to fix it
thanks 

For audio work you already own a perfectly satisfactory signal generator - the sound output of your PC.  There is free software to put an image on screen and give you controls similar or identical to a standalone signal generator.

but what software would it be? I have audacity on the pc, in fact it could be useful.
I see that you always combine the sine wave with audio systems. But the signals created by a generator are not only used for sound cards, but also for other I guess ..
thanks

If you're worried about the risks and limitations of your PC audio output then you can generate your own test CD to use with your CD player. Either generate the tracks from scratch using an audio editing package, or use an already available one, eg: https://www.head-fi.org/threads/free-audio-test-cd-to-download.225325/
EDIT: Still available on archive.org:  https://web.archive.org/web/20041012012055/http://www.virtuelvis.com/download/201/testcd.7z

but is it therefore highly risky for the PC to generate signals from a PC?
 
thanks

[rstofer]

Here's a thread on the Uni-T UTG932 Function Generator (AWG) - $139 at Amazon and it looks like a really nice piece of equipment:

https://www.eevblog.com/forum/testgear/uni-t-utg932utg962-200msas-function-arbitrary-waveform-generator-220394/msg2807932/#msg2807932

https://www.amazon.com/Waveform-Generator-Arbitrary-Function-Sampling/dp/B0819W89DH

Here's a link to the User Manual.  It is also available from a link on the lower left portion of the Amazon page.

https://m.media-amazon.com/images/I/D1z-10A+LSS.pdf

[rstofer]

but is it therefore highly risky for the PC to generate signals from a PC?

In my view, yes. Particularly if the sound components are mounted to the PC motherboard.  And quadruple the risk for 'troubleshooting'.

There's a difference between 'troubleshooting' and 'electronic design/build' in that it may not always be known what is going on inside some piece of equipment you didn't design/build.  There just might be some voltages that are not healthy for the PC.  In the design/build category, the hobbyist should know exactly what voltages are present and where.

That you want to do troubleshooting is the main reason I don't keep talking about the Analog Discovery 2 because it is a superior solution for a bench full of test equipment.  However, when using the fly leads, the allowable voltage range is +-25V (50V differential) and I could imagine a situation where some arbitrary piece of equipment had voltages outside this range.  Now, true, I could work around it with the BNC adapter and 10x probes but I'm not going to go around praising the device when the end application is troubleshooting.

If the topic was 'learning electronics' or 'experimenting with circuits <= 15VDC", I would be talking about the AD2 in every thread.

There is no condition under which I would use a PC for a tone generator.  PCs cost too much!

I'm not all that happy using USB either so I run it through a powered hub in the great hopes of protecting the PC.  And I don't play with higher voltages...

[CharlotteSwiss]

Here's a thread on the Uni-T UTG932 Function Generator (AWG) - $139 at Amazon and it looks like a really nice piece of equipment:

this has a reasonable price (of uni-T I also have a DMM and I found myself well, my father also has the economic clamp meter and it doesn't look bad, it takes us enough)
 

[CharlotteSwiss]

but is it therefore highly risky for the PC to generate signals from a PC?

In my view, yes. Particularly if the sound components are mounted to the PC motherboard.  And quadruple the risk for 'troubleshooting'.

There's a difference between 'troubleshooting' and 'electronic design/build' in that it may not always be known what is going on inside some piece of equipment you didn't design/build.  There just might be some voltages that are not healthy for the PC.  In the design/build category, the hobbyist should know exactly what voltages are present and where.

That you want to do troubleshooting is the main reason I don't keep talking about the Analog Discovery 2 because it is a superior solution for a bench full of test equipment.  However, when using the fly leads, the allowable voltage range is +-25V (50V differential) and I could imagine a situation where some arbitrary piece of equipment had voltages outside this range.  Now, true, I could work around it with the BNC adapter and 10x probes but I'm not going to go around praising the device when the end application is troubleshooting.

If the topic was 'learning electronics' or 'experimenting with circuits <= 15VDC", I would be talking about the AD2 in every thread.

There is no condition under which I would use a PC for a tone generator.  PCs cost too much!

I'm not all that happy using USB either so I run it through a powered hub in the great hopes of protecting the PC.  And I don't play with higher voltages...

ok exhaustive explanation, it is not my intention to use the pc to generate the signals. 
But even with the 1khz online sine wave that I used to verify the out of that sound card that I repaired, did I risk losing my PC?
  

[rstofer]

ok exhaustive explanation, it is not my intention to use the pc to generate the signals. 
But even with the 1khz online sine wave that I used to verify the out of that sound card that I repaired, did I risk losing my PC?

It depends on the voltages involved on the sound card.  If it was just +-12V, or something like that, probably not.  I'm just guessing that the PC audio output is capacitively coupled so even shorting the leads probably won't damage anything.  If the audio is DC coupled then, yes, there is a risk of damage by a short circuit.

But just let the test leads hit the mains in the power supply section of a commercial amplifier and all bets are off!

Then there is the 'ground' problem.  Where exactly is it ok to hook the ground side of a single-ended audio source?  Remember, one side of that source may be at earth ground if the PC has an earth ground connection (like most desktops).  This is also a problem with bench type AWGs.  That pesky BNC shell is at earth ground potential!

I don't do audio so I don't have a lot of experience inside commercial equipment.  Nevertheless, I will stick to the idea that there is no condition under which I will risk my laptop or PCs by using them for tone generation.  Why risk a laptop costing a couple of thousand dollars when I can buy a really nice AWG for $139?  Or a less capable one for < $50?  I can blow up a bunch of $50 signal generators for what this laptop cost!

That said, I might consider generating tones with a Raspberry Pi.  I have a bunch of them and messing one up isn't all that expensive.

[CharlotteSwiss]

ok exhaustive explanation, it is not my intention to use the pc to generate the signals. 
But even with the 1khz online sine wave that I used to verify the out of that sound card that I repaired, did I risk losing my PC?

It depends on the voltages involved on the sound card.  If it was just +-12V, or something like that, probably not.  I'm just guessing that the PC audio output is capacitively coupled so even shorting the leads probably won't damage anything.  If the audio is DC coupled then, yes, there is a risk of damage by a short circuit.

But just let the test leads hit the mains in the power supply section of a commercial amplifier and all bets are off!

Then there is the 'ground' problem.  Where exactly is it ok to hook the ground side of a single-ended audio source?  Remember, one side of that source may be at earth ground if the PC has an earth ground connection (like most desktops).  This is also a problem with bench type AWGs.  That pesky BNC shell is at earth ground potential!

I don't do audio so I don't have a lot of experience inside commercial equipment.  Nevertheless, I will stick to the idea that there is no condition under which I will risk my laptop or PCs by using them for tone generation.  Why risk a laptop costing a couple of thousand dollars when I can buy a really nice AWG for $139?  Or a less capable one for < $50?  I can blow up a bunch of $50 signal generators for what this laptop cost!

That said, I might consider generating tones with a Raspberry Pi.  I have a bunch of them and messing one up isn't all that expensive.

then just signals from the pc, think that I had left a jack cable connected .. to learn with sine and square waves ...
i think someone from heaven assisted me, i had no damage to my asus motherboard
I think I will focus on uni-T ...
Leaving out the sound cards, a signal generator on what other jobs could serve? (just in 4 words) because I have to understand that it can be used for many checks of small parts of the circuit ...
thank you 

[rstofer]

From what little I know about troubleshooting audio equipment, it would seem that anything that generates some kind of audio signal is adequate.  Jam a signal into an amplifier and trace it through to the output.  Pretty easy stuff for ANY generator.  Making detailed measurements, like THD, probably takes something better but I don't know that!

Your interests seem to lie strictly in troubleshooting not in electronics itself.  If so, don't spend much on a signal source because it isn't necessary.  When/if you get interested in learning electronics (generally) or in designing things like filters or amplifiers, a better AWG will be a tremendous help.  Actually, if you decide to take up 'learning electronics', I'm going to get back to recommending the AD2.  It is absolutely the right answer to learning and designing things.  It's actually good that you have the scope because you can scope signals while the AD2 is running a Bode' plot (amplitude and phase versus frequency).  Still, the AD2 is a niche device, aimed at college students.  It's nice to be able to carry an entire lab in your backpack.

One thing an AWG can do is generate AM and FM signals if that is of interest in troubleshooting.  They might also be helpful for alignment.

Generating square waves is helpful for digital circuits but I would have to think a long while to recall ever using triangle or ramp waveforms.  I guess they could be good for testing analog circuits like comparators or even integrators (square wave might be better).

I have a lot of interest in analog integrators for analog computing.  It's old school but it is making a comeback.  Analog comuting defines the concept of 'real time computing'.

[james_s]

If you just want a signal for testing audio gear, a Wein-bridge oscillator is a classic solution which can be built out of an op amp and a handful of passives. Lots of old analog function generators out there that you can pick up cheaply too, even a very basic one is more than adequate for the task. In a pinch you can just use a CD player, MP3 player, an old mobile phone or anything else that can play an audio file if you are the slightest bit concerned with damaging your PC by using that as a source.

[Gyro]

If you're worried about the risks and limitations of your PC audio output then you can generate your own test CD to use with your CD player. Either generate the tracks from scratch using an audio editing package, or use an already available one, eg: https://www.head-fi.org/threads/free-audio-test-cd-to-download.225325/
EDIT: Still available on archive.org:  https://web.archive.org/web/20041012012055/http://www.virtuelvis.com/download/201/testcd.7z

but is it therefore highly risky for the PC to generate signals from a PC?
 
thanks

No, you're only using the PC to burn a CD.

[CharlotteSwiss]

From what little I know about troubleshooting audio equipment, it would seem that anything that generates some kind of audio signal is adequate.  Jam a signal into an amplifier and trace it through to the output.  Pretty easy stuff for ANY generator.  Making detailed measurements, like THD, probably takes something better but I don't know that!

Your interests seem to lie strictly in troubleshooting not in electronics itself.  If so, don't spend much on a signal source because it isn't necessary.  When/if you get interested in learning electronics (generally) or in designing things like filters or amplifiers, a better AWG will be a tremendous help.  Actually, if you decide to take up 'learning electronics', I'm going to get back to recommending the AD2.  It is absolutely the right answer to learning and designing things.  It's actually good that you have the scope because you can scope signals while the AD2 is running a Bode' plot (amplitude and phase versus frequency).  Still, the AD2 is a niche device, aimed at college students.  It's nice to be able to carry an entire lab in your backpack.

One thing an AWG can do is generate AM and FM signals if that is of interest in troubleshooting.  They might also be helpful for alignment.

Generating square waves is helpful for digital circuits but I would have to think a long while to recall ever using triangle or ramp waveforms.  I guess they could be good for testing analog circuits like comparators or even integrators (square wave might be better).

I have a lot of interest in analog integrators for analog computing.  It's old school but it is making a comeback.  Analog comuting defines the concept of 'real time computing'.

follow a signal in an audio circuit I knew it, maybe for the moment I would need very little in fact, I know that I could initially take something really basic, of course the signals will be low frequency, to find where a circuit has a problem, I guess you don't need high frequency signals ..
thank you 

If you just want a signal for testing audio gear, a Wein-bridge oscillator is a classic solution which can be built out of an op amp and a handful of passives. Lots of old analog function generators out there that you can pick up cheaply too, even a very basic one is more than adequate for the task. In a pinch you can just use a CD player, MP3 player, an old mobile phone or anything else that can play an audio file if you are the slightest bit concerned with damaging your PC by using that as a source.

ah here, for the learning tests then I put some sinusoidal signal on my mp3 player, thanks for the suggestion.
 

No, you're only using the PC to burn a CD.

ok, but then I only have two cd players inside the pc, so we are point to head to send the signal
 

[Gyro]

No, you're only using the PC to burn a CD.

ok, but then I only have two cd players inside the pc, so we are point to head to send the signal
 

I'm sure there used to be other devices that could play audio CDs, now what were they called? I'm sure I've got one. 

Try ebay (or local charity shop)

[CharlotteSwiss]

I'm sure there used to be other devices that could play audio CDs...

sure, but I'm equally aware that I don't have that device at home...
 

[CharlotteSwiss]

if I understand correctly, the most frequent use of the signal generator is for those who design and create electronic circuits, to do the signal tests during the project finishing phase